1. Field of the Invention
The present disclosure relates to a wiring board unit including a wiring board and a lead frame having the wiring board within an opening, a manufacturing method of the wiring board unit, and a manufacturing method of a wiring board with lead obtained subsequently to the manufacturing method of the wiring board unit.
2. Description of Related Art
For example, Japanese Patent Application Laid-open No. 2001-156215 (Pages 1 to 8, FIGS. 1 to 4) proposes a technique for obtaining a ceramic package. In this technique, the resulting ceramic package includes a lead frame and a ceramic board. The lead frame has a plurality of lead units extending in parallel with each other from one side of an opening having a rectangular shape in top view to inside of the opening. In the ceramic board, a terminal is fixed at each end of the lead units by brazing. Furthermore, this ceramic board is supported in a cantilever manner at the required position within the opening. A seal ring is fixed on a primary surface of a ceramic layer of the ceramic board. Outer shape of the seal ring is used as the reference of the position recognition to mount a semiconductor device on the ceramic board. Thus, the ceramic package superior in mounting accuracy and productivity can be obtained.
In the ceramic package disclosed in Japanese Patent Application Laid-open No. 2001-156215, however, the leads within the opening of the lead frame are configured to support the ceramic board in a cantilever manner. Such a configuration of the ceramic package may cause matters as described below. That is, a plating step is performed after a mounting step for mounting the ceramic board to the lead frame. In the plating step, the surface of the terminal and/or the leads of the ceramic board are covered with a metal plating film. In this plating step, the ceramic board tends to swing in a flowing plating solution. Thus, the leads may be bent and deformed. In particular, when the leads are thin and small in width, the leads is more likely to be bent and deformed. As a result, defect products could be caused in the resultant wiring board unit or leaded wiring board that is a lead frame with the wiring board.